Railway signaling



April 8 1924. '1,49,$60

E. S. TIDDEMAN RAILWAY SIGNALING Filed July 24. 1920 2 Sheets-Sheet a Apvifi 8 1924-. 1, 39,860

E. S. TIDDEMAN RAILWAY SIGNALING Filed July 24. 1920 2 Sheets-Shaw, 2

Patented Apr. 8, 1924s UlsllTE STAT treats EDMUND SPENSER, TIDDEMAN, 9F IFELIEZES, HDRNCI-IURCH, ENGLAND, AS-

SIGNOR 10 W. R. SYHES INTEELQCKING SIGNAL COEZEANY LIMITED, 6F CLAPHAM,

LOEDON, ENGLAN'D.

BAIL A1 SIGNALING.

Serial No. 398,788.

(GRANTED UNDER, THE ERGVIHQNS 05 THE ACT OF MAEGH 3, 1921, -l STAT. L, 1313.)

1 all iii/tom it may concern:

Be it known that I, EDMUND SrnNsER TrnnmniN, of Wood End, Great Nelrnes, l lornchurch, in the county of Essex, England, a subject of the King of Great Britain, have invented certain new and useful Improvements in Railway Signaling, (for which I have filed an application in England, March 19th, 1919, Patent- No. 135,-

10 743), of which the following is a specification.

This invention relates to apparatus for automatically controlling railway traiiic more particularly to that type of such apparatus which includes an electrically conductive track-ramp and a co-operating plun er and shoe carried by the locomotive or other Vehicle whereby the operation of the brakes is automatically controlled in accordance wi h the electrical condition of the ramp as governed by the position of a co operating road signal.

The object of he invention is to provide an improved track layout including means for enabling a locomotive to be backed or,

i in some cases, run forward over a ramp, notwithstanding that the signal to which such ramp appertains happens to be standing at line blocked, without the brakes being in consequence applied; it being frequently desirable that such freedom should be afforded when, for example, shunting operations are being performed.

An example of the present invention, as applied to a singleline railway, is illustrat ed diagrammatically in the accompanying erawings, wherein Figures 1 and 2 show the stateof the electrical connections when the road signal, with which the track ramp is adapted to co-operate,v is standing at line clear and line blocked respectively; the track-ramp being unoccupied by a train.

in systems of the kind to which the present invention relates the locomotive (or other vehicle) 17 carries an upright plunger a fitted to slide vertically through a guide (1 and tending (under the stress of a spring,

not shown) to assume a bottom limit position wherein an electrisally-conductive shoe 16 at the lower extremity of the plunger can so encounter a track-ramp as to be raised thereby during the passage of the locomotive overthe ramp. The shoe 16 is in per manent electrical connection (as for example, through the plunger (4 and a station ary contact-piece 0 with which the plunger is in constant frictional contact) with one pole of the winding of an electromagnet s, hereinafter termed the locomotive electromagnet, also with one polar terminal of an electric bell w, and further with one pole of the winding of a polarized relay it, hereinafter referred to as the locomotive polarized relay, the electromagnet 8, bell w, and relay it being all carried by the 1000- B5 motive 17. lhe other pole of the winding of the electromagnet s and the other pole of the winding of the relay u are both permanently earrhed at t, whilst the other polar terminal of the bell w is permanently connected to the switch-tongue o of the relay u. i

The shoe 16, as it passes in either direction over the track-ramp, is always mechanically raised thereby, and therefore thrusts up-- 75 wards the plunger (6, to a corresponding extent, it being understood that the extent of such upward movement must exceed a pre letermined limit in order to bring about the application of the brakes. If on the one hand. when the plunger a is raised, the electromagnet s happens to be tie-energized owing to the ramp being electrically dead in consequence of the road signal standing at line blocked, the rise of the plunger 85 n will be permitted to bring about, by mechanical means provided on the locomotive 17 but not shown the application of the brakes and the giving of a danger signal in the cab of the locomotive. If, on the other hand, when the plunger a is raised, the electromagnet s happens to be energized owing to the ramp beingelectrically charged with current of either polarity in consequence of the road signal standing at line clear, the electromagnet will attract its armature p and, by means not shown, will prevent the application of the brakes and the giving: of a danger signal in the cab. The track-ramps which (on a single-- line railway, as in the example shown) control traflic in opposite directions are adapted to be charged with current of different polarities respectively, the polarities of the respective ramps being such that, during the passage of the shoe 16 over a trackrainp appertaining to any road signal which controls traffic in the direction wherein the train is proceeding forwards, the bell to will be rung in consequence of the energization of the polarized relay it having for effect to move the switch-tongue c) from the normal inoperative position shown, to the position wherein, by hearing against a peruianently-earthed contact this tongue completes the circuit of the bell, the tongue '1) remaining, however, unaffected when the shoe 16 passes over a track-ramp appertaining to any road-signal which controls traiiic in the opposite direction.

All the above described instrumentalities and operations are substantially as described in the specification of the co-pending application Serial No. 398,786 filed July 2lth, 1920. The improved track layout will now be described which forms the subject of the present application. and which is adapted to permit of a locomotive being run backwards over a track-ramp w' hout the brakes being in consequence applied, inotwithstanding that the road signal with which such ramp co-operates is standing at line blocked.

As will be seen on reference to the draw ings, the track-ramp (which may be made a few feet longer than heretofore) comprises two sections 11 and 12 which are electrically insulated from one another at 13; the longer or main ramp-section 11 comprising the summit 14: and that end 15 of the ramp which is the first to be encountered by the plunger shoe 16 when the locomotive 17 passes over the ramp in the normal or forward direction of running as indicated by the arrow A; whilst the other section 12, hereinafter termed the ramp extension, comprises that end 18 of the ramp which is the first to be encountered by the plunger-shoe when a locomoitve is backed over the ramp in the direction indicated by the arrow B. The main ramp section 11 is electrically charged, during normal working, only when the road signal 19 stands at line clear (as in Figure 1), so that this section 11 is adapted normally to perform the functions of the undivided ramp hitherto employed, whereas the ran'ipextension 12 is electrically charged only when the signal 19 stands at line blocked (as in Figure 2), so that this section 12 is adapted to restrain the application of the brakes during the first part of the backward passage, over the ramp, of the plunger-shoe 16 on the locomotive; whilst means are provided for automatically causing the main ramp-section 11 to become electrically charged during the remainder of such backward passage of the plungershoe, and thus ensuring the continued restraint of the brakes throughout the entire backward movement of the locomotive 17 over the ramp.

For the purpose of transn'iitting current through the respective ramp-sections, two independent electric batteries are employed, or the connections from asingle source of current are so arranged as to produce an ellect equivalent to that of such separate batteries For the sake of convenience it will hereinafter be assumed that two independent batteries 21 and 22 are provided, one for each ramp-section 11 and 12.

The battery 21 (hereinafter termed the main ramp-battery), which corresponds to the usual single ramp-battery as regards the functions fulfilled in normal working, has one of its poles (say the positive pole) connected to the main ramp-section 11 through a pair of contacts 23, 2st which are bridged by a switch 20 only when the signal 19 stands at line clear, this (positive) pole being connected to earth through a pair of contacts 25, 26, which are bridged by the switch 20 only when the signal ,JtlS at line blocked, The opposite (i. e. negative) pole of the battery 21 is connected to earth through a pair of contacts 27, 28 whichare bridged by a switch 29 only when the signal 19 stands at line clear, and to the main ramp-section 11 through two switches in series with one another;

that is to say, on the one hand through a pair of contacts 30, 31 which are bridged by the switch 29 only when the signal 19 stands at line blocked, and on the other hand through a switch so controlled by a stationary non-polarized relay (which may he installed in the signal-cabin) as to be closed only when, the switch 29 being already closed, the plunger shoe 16 of. the locomotive 17 is being backed over the ramp.

1e battery 22 (hereinafter termed the ramp extension battery) has one of its poles (in the case assumed, the negative pole) permanently connected to the rampcxtension 12, whereas the opposite (i. c. positive) pole is connected to earth through the coil 37 of the non-polarized relay 38 and a pair of contacts 8 1-, 35, which are bridged by a switch 36 closed only when the signal 19 stands at line blocked.

The connections appertaining to the two batteries areso arranged that whereas the ramp-extension battery 22 always has the saine pole (in the case assumed, the negative pole) directly connected to the rampextension 12, the main rampbattery 21 has its negative pole connected to the main ramp-section 11 (by way of the relayswitch 32) so long as the signal 19 stands at line blocked, but has its positive pole connected to said main ramp-section 11 when the signal stands at line clear. lence the ramp-extension 12, which is electrically alive only when the signal 19 stands at'line blocked, can in such circumstances transmit only current of negative polarity through the plunger shoe 16 and locomotive electro-ma-gnet s, such cur rent being prevented, by the locomotive polarized relay u from ringing the bell w in the cab, The main ramp-section 11 how ever is capable on the one hand of trans mitting current of positive polarity through the plunger-shoe 1t and locomotive electroinae'net s when the signal 19 stands at line c r, such current being permitted, by the locomotive polarized relay a, to ring the bell w in the cab; and is also capable on the other hand of transmitting current of negative polarity (by way of the relayswitch 32 if this be closed) when the sig nal 19 stands at line blocked.

The stationary non-polarized relay 33 above mentioned has two windings 3'? and 38 each of which is in circuit with one of the ramp sections 11, 12 and also independently capable, when energized, of effecting the closure of the relay-switch 32; the wind-- ing 37, which is in circuit with the rainp-ex tension 12, being interposed between the ramp-extension battery 22 and the contact 3 1 of the switch 36 whereby the positive pole of said battery is earthed when the signal .19 stands at line blocked; whilst the winding 38, which is in circuit with the niain ramp section 11, is interposed in the connection between said main ramp-section and the closing contact 39 of the relay switch 82 itself.

The switches 20, 29 and 36 above referred to may be mechanically actuated and in the example illustrated are shown as operated by means of the usual signal hand-lever 40 in the cabin; or they might be actuated by the signal-arm 19 itself, or byisome part inoving as one with either said arm or said handlever 40 T he length of the ramp-extension 12 should be limited to an end portion of the ramp so low as'to be incapable,when the locomotive 17 is being backed over the ramp in the direction of the arrow B, of liftingv the shoe 16 and plunger a on the locomotive to the height required for bringing aboutthe application of the brakes. V

In normal working, if the signal 19 is standing at line clear; the plungenshoe 1630f a locomotive 1? which passes o er the amp in the forward direction (indicated by the arrow A) will find the main ramp-section 11 charged with current i of positive polarity, so that current of this polarity will pass from the main ramp-battery 21 not only through .the bell-circuit by way of the locomotive polarized relay it, thus causing the bell to to ring, but also through the locomotive electromagnets, thusenergizing the latter and restraining the application of the brakes notwithstanding that the plunger (4 is fully raised by the shoe 16 passing the summit 1 1 of the ramp. As the plunger shoe 16 there after passes forward, it finds the ramp-e3;- tension 12 electrically dead, so that the 10- comotive electromagnet s will cease to be energized; but, as the height of the ramp-extension 12 is insufficient for bringing about the operation of the brake-applying mechanism, the locomotive 17 will remain free to travel forward clear of the ramp.

If, however, the signal 19 is standing at line blocked, the plunger-shoe 16, on passing over the ramp in the forward direction, will find the main ran1psection 11 electrically dead, so that no current will pass either through the boll-circuit or through that of the locomotive electroinagnet s, and hence the lifting of the plunger will be able to bring about the operation of the brakeapplying mechanism. As the plunger-shoe 16 thereafter passes forward (unless the '10- coniotive is already brought to rest) it finds the ramp-extension 12 electrically charged, but with current of negative polarity, so that whilst the locomotive polarized relay to will prevent the bell w from being rung, the locomotive electromagnet s will be energized. This however, will not interfere with the application of the brakes which, when once appied, can only be released by the driver. The. closing of the circuit oft-he ramp-extension battery 22 always causes the wind ing 3? of the stationary non-polarized relay to be energized, but although this will result in the main ramp-section 11 becoming electrically charged in consequence of the closure of the relay-switch 32 so long as the plungereshoe 16 remains in contact with the ram -extension 12, the application of the brakes will not be interferedwith, for the reason that the plunger-shoe 16 is no longer in contact with the main ramp-section 11.

If, new, the locomotive 17 should be backed over the ramp whilst the signal 19 is standing at line blocked, the plungershoe 16, will find the ramp-extension 12 electrically charged with current of negative polarity, so that a negative currentv will pass through the circuit the locomotive electromagnet s, the ramp-extension battery 22, and the winding 37 of the non-polarized relay Hence, althoughthe locomotive polariaed relay @4- will preventvthe bell from being rung, the locomotive electromagnet a will be energized and;the plunger a, even if lifted highenough, will be prevented from bringing about the operation of the brake-apply ing mechanism, The closing of the circuit of the ramp-extension battery 22 causes the winding 3'? of the relay 83 to be energized, so that the 1llY-SW1tCl132 will be closed with the result that the main ramp-section '11 will be charged with current of negatlve polarity from the main rampbattery 21.

Hence when the plunger-shoe 16 reaches the main ramp-section 11, the other winding 38 of the relay o3 will become energized by current from the main ramp-battery 21 and will continue to hold the relay-switch 32 closed notwithstanding that the winding 37 becomes de-energized on the plunger-shoe 16 passing out of contact with the ramp-extension 12. Therefore the energization of the locomotive electromagnet s will be main tained, and the plunger a will still be prevented from bringing about the operation of the brake-applying mechanism, so that the locomotive will be enabled to pass in the rearward direction clear of the ramp.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. In railway traffic-controlling apparatus the combination of a road signal, means for operating the same, a conductive shoe carried by a train, a track-ramp adapted to be engaged by said shoe and comprising a main ramp-section and a ramp-extension mutually insulated and so placed as to be respectively first encountered by said shoe as said train travels forward or backward and means co-operating with said signal operating means, whereby said main ramp-section alone is electrically charged when said road signal stands at line clear and whereby said ramp-extension alone is electrically charged when said signal stands at line blocked and whereby said main ramp section is electrically charged during the backward travel of said conductive shoe over it when said signal stands at line blocked.

2111 railway traific-controlling apparatus, the combination of a road signal, means for operating the same, a conductive shoe carried by a train, a track-ramp adapted to be engaged by said shoe and comprising a main ramp-section and a ramp-extension mutually insulated and so placed as to be respectively first encountered by said shoe as said train travels forward or backward, and electric means co-operating with said signal-operating means whereby, when the roadsignal stands at line clear, said main ramp-section alone is charged with electric current of predetermined polarity, whereas, when the road signal stands at line blocked, said ramp-extension alone is initially charged with current of the opposite polarity, whilst the main ramp-section is charged with current of said opposite polarity as a result of the train being backed over the ramp, substantially as set forth.

3. Railway traffic-controlling apparatus as claimed in claim 2, wherein two separate sources of electric current are provided, the

ramp-extension being permanently connected with one pole of the one source of current, whilst the main ramp-section is adapted to be connected with the corresponding pole of the other source of current or with the opposite pole thereof, according as the road-signal stands at line blocked or line clear.

4. In a railway traflic-controlling apparatus the combination of a road signal, means for operating the same, a conductive shoe carried by a train, a track-ramp adapted to be engaged by said shoe and comprising a main ramp-section and a ramp-extension mutually insulated and so placed as to be respectively first encountered by said shoe as said train travels forward or back ward, two separate sources of electric current one pole of one of which is permanently connected with the ramp-extension, a re lay having two windings in circuit respectively with the two ramp sections, and switches controlled respectively by said relay and by the signal-operating means to cause the main-ramp-section to be connected with the corresponding pole of the other source of current or with the opposite pole thereof according as the road-signal stands at line blocked or line clear.

5. The combination, with railway traincarried trafiic-controlling apparatus of the known kind referred to and including a conductive movable shoe mounted on the train, of a road-signal installed beside the railway track, a track-ramp comprising two electrically-conductive and mutually insulated sections, namely, a main ramp-section and a ramp-extension so placed relatively to one another as to be respectively adapted to be first encountered by said shoe according as the train is travelling forward or backward, means for causing the main ramp-section alone to be electrically charged when the road signal with which the ramp is adapted to co-operate stands at line clear, for causing the ramp-extension alone to be charged when said signal stands at line blocked, and for automatically causing the main ramp-section to become charged during the backward passage of said conductive shoe over it when the signal stands at line blocked, for the purpose set forth.

6. The combination, with railway traincarried traffic-controlling apparatus of the known kind referred to and including a conductive movable shoe mounted on the train, of a road-signal installed beside the railway track, a trackramp comprising two electrically-conductive and mutually insulated sections, namely, a main ramp-section and a ramp-extension so placed relatively to one another as to be respectively adapted to be first encountered by said. shoe according as the train is travelling forward or backward, means for causing the main ramp-section alone to be electrically charged when the road signal with which the ramp is aeasco adapted to co-operate stands at line clear, for causing the ramp-extension alone to be charged when said signal stands at line blocked, and for autoniatically causing the main ramp-section to become charged during the backward passage of said conductive shoe over it when the signal stands at line blocked, said means comprising two separate sources of electric current, a non-polarized relay having two windings, switcheswhereof the condition is dependent upon the indication given by said road-signal, and electrical interconnections between said sources of current and the switches, the re lay, and the sections of the ramp, substantially as and for the purpose set forth.

7. The combination, with railway traincarried traffic-controlling apparatus of the known kind referred to, of a track-ramp comprising two mutually-insulated sections, a road-signal, electric batteries, a switch with a plurality of contacts, a second switch having a plurality of pairs of contacts, a third switch having a plurality of pairs oi contacts, means for controlling said switches in accordance with the indication given by the signal, a relay switch, a non-polarized relay having two windings and controlling said relay switch, and electrical connections substantially as described.

8. In railway trafic-controlling apparatus, the combination of a track-ramp comprising a main ramp-section and a ramp-extension insulated therefrom, a road-signal, an operating lever therefor, a first electric battery, a second electric battery, a nonpolarized relay having two windings and whereof one is connected through said second battery with the ramp-extension and the other winding is connected with the main rampsection, a normally open switch controlled by said relay, a second switch controlled by the lever for earthing the ramp -extension through said second battery and said one winding when the signal stands at line blocked, and additional switches controlled by said lever for earthing the main rampsection through said first battery in one direction when the signal stands at line clear and in the opposite direction through said other winding and normally open switch when the latter is closed and said signal stands at line blocked, substantially as described.

EDMUND SPENSER TIDDEMAN. 

